巻号一覧
40 巻, 7 号
選択された号の論文の17件中1～17を表示しています
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沖中 秀行1993 年 40 巻 7 号 p. 668
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (83K) -
亀山 一郎, 加賀田 博司, 加藤 純一, 井上 竜也1993 年 40 巻 7 号 p. 669-672
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーWe have investigated the substitution of Zn for Ca in Bi2O3-CaO-Nb2O5 system in order to improve the dielectric constant at microwave frequencies. CuO was added to lower sintering temperature. The refined composition was represented as 40.5BiO3/2-23.2(Ca.75 Zn.25)0-36.3NbO5/2 containing 0.2 wt% CuO. This ceramics could be sintered at 925°C and had excellent dielectric properties ; ε=95, Q=660(at 2.9GHz), and τf=+1ppm/°C. It is applicable to multilayer microwave devices with Ag Inner conductors.抄録全体を表示PDF形式でダウンロード (220K) -
石崎 正人, 景山 恵介1993 年 40 巻 7 号 p. 673-676
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーThis paper describes Q factors of dielectric resonators for quasi-microwave filters. Dielectric resonators are composed of dielectric ceramics with different εr or tanδ and cylindrical cavities with different dimensions. Measured resonant frequencies and Q factors of dielectric resonators are compared with computed value by FEM and incremental frequency rule. As a result, low-loss dielectric ceramics are effective when Qd(the dielectric Q factor) is dominant for Q factor of dielectric resonator. In this case, the dielectric resonator with Qu=65000 is realized by using Ba(Zn1/3Ta2/3)O3-(Sr, Ba)(Ga1/2Ta1/2)O3. On the other hands, reducing conductor losses with using high εr dielectric ceramics are effective when Qc(the Q factor of conductor) is dominant for the Q factor of whole dielectric resonator.抄録全体を表示PDF形式でダウンロード (228K) -
野村 武史, 人見 篤志, 佐藤 陽, 中野 幸恵1993 年 40 巻 7 号 p. 677-681
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーDegradation behavior of insulation resistance of BaTiO3 based Ni-electrode multilayer ceramic capacitors has been studied with special reference to the dielectric composition and grain boundary chemistry. The degradation behavior shows clear dependence on A/B of grain boundary layer. It is shown that SiO2 extracts BaO and Cat) from (Ba1-XCaXO)m(Ti1-YZrYO2) and then A/B of grain boundary layer become less than the unity. We have developed high capaci-tance multilayer ceramic capacitors as 10.5μF in 3216 type with superior reliability, using newly developed dielectric material, (BaO)m(Ti1-YZrYO2)+aMnO+bY2O3+cV2O5+dWO3 (Y=0.18, m=1.004, a=0.2wt%, b=0.3wt%, c=0.04wt%, d=0.05wt%).抄録全体を表示PDF形式でダウンロード (3227K) -
Junichi Hojo, Hideyuki Emoto1993 年 40 巻 7 号 p. 682-686
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーBaTiO3-Ni mixed powders were sintered at 1300°C in Ar and the microstructures and electric properties of sintered bodies were investigated with emphasis on the effects of particle size of starting powders. Ni particles dispersed better in BaTiO3 matrix in BaTiO3(0.02μm)-Ni(4-7μm) system, in which the electric resistance was kept high at a large Ni content and the dielec-tric constant increased remarkably with increasing Ni content. On the other hand, Ni particles coalesced in BaTiO3(0.1μm)-Ni(4-7μm) systems at a small Ni content, resulting in a decrease in electric resistance. The significant growth of Ni particles was observed in BaTiO3(0.02μm)-Ni(0.02μm) system. It is concluded that the combination of coarse Ni and ultrafine BaTiO3 particles is effective to produce the dielectric composites, because Ni particles are coated with finer BaTiO3 powder on the mixing process.抄録全体を表示PDF形式でダウンロード (6119K) -
大内 宏, 西田 正光1993 年 40 巻 7 号 p. 687-692
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーSolid solution ceramics of the system xPb(Mg1/3Ta2/3)O3-yPbTiO3-zPbZrO3 were prepared by the solid state reaction of powder materials. Ceramic, dielectric, and piezoelectric properties and crystal structures of the system were studied. The system is composed of four crystal phases at room temperature: the cubic, pseudocubic, tetragonal, and rhombohedral. Sintering of the system xPb(Mg1/3Ta2/3)O3-yPbTiO3-zPbZrO3 is much easier than that of each end compositions and a well sintered high density ceramics was obtained for the compositions near the morphotropic transformation. Piezoelectric ceramics with high relative dielectric constants and high radial coupling coefficient and low resonant resistance were obtained for the composition near the morphotropic transformation. The composition Pb(Mg1/3Ta2i3)0.125-Ti0.435Zr0.44O3 showed the highest radial coupling coefficient.抄録全体を表示PDF形式でダウンロード (340K) -
増本 博, 滑川 政彦, 山根 久典, 平井 敏雄1993 年 40 巻 7 号 p. 693-696
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーBismuth titanate (Bi4Ti3O12) thin films were prepared above 700°C on sapphire (1120) substrates by chemical vapor deposition using tri-phenyl-bismuth[Bi(C6H5)3] or tri-ortho-tolyl-bismuth [Bi(o-Tol)3] as Bi sources and titanium-tetra-isopropoxide [Ti(i-C3H7O)4] or di-isopropoxy-bis-(dipivaloyl metanato)-titanium [Ti(i-C3H7O)2(DPM)2] as Ti sources. The Bi4Ti3O12 films showed preferred orientation of (001) parallel to (1120) of sapphire substrate. The epitaxial relationship between sapphire ‹0001› and Bi4Ti3O12‹100› was observed for the Bi4Ti3O12 films prepared at 850°C.抄録全体を表示PDF形式でダウンロード (1283K) -
齊藤 格, 北野 博久, 豊田 幸夫, 大西 康司1993 年 40 巻 7 号 p. 697-700
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーBy using a precision dicing-machine, we obtained the unique structure of PLZT optical shutter element having a 3-dimensional electrode and achieved low driving voltage of shutters. As a result, we have created a prototype PLZT optical shutter array with resolution of 400dpi, print width up to 300mm and a few micro second switching time, and its printing has been succeeded.
It is expected that the PLZT optical shutter array will be a telling device for development of a high speed electophotographic printer and a full-color printer using silver halide photography and so on.抄録全体を表示PDF形式でダウンロード (1531K) -
Takashi Goto, A.R. West1993 年 40 巻 7 号 p. 701-704
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーThe electrical conduction mechanism for defect-perovskite LaTa3O9 was studied by D.C. polarization technique. The linear log (σdc) vs (time)-1/2 relationship was observed, which means that diffusion process could be dominant for the electrical conduction. Total stored charges increased with increasing temperature depending on oxygen partial pressure (PO2). Asymmetrical polarization measurements showed that the polarity of the electrode affected to the time dependence of σdc and leakage currents. The relationship between D.C. voltage and the leakage currents suggested that dominant electronic charges might change from electrons to holes with increasing temperature and PO2.抄録全体を表示PDF形式でダウンロード (210K) -
香山 滉一郎, 森下 政夫1993 年 40 巻 7 号 p. 707-712
発行日: 1993/07/15
公開日: 2009/12/04
ジャーナル フリーA new method was developed to prepare rare earth oxide dispersion tungsten powder, and some sintering characteristics of the powder were investigated. The results are as follows :
(1) Rare earth oxide dispersion tungsten powder can be prepared by spraying an acetic acid aqueous solution of ammonium tungstate para pentahydrate and lanthanum (III) oxide.
(2) Rare earth oxide is dispersed as fine particles in tungsten matrices of sintered specimens. This finding contrasts with the fact that the conventional V-Blender mixing gives sintered specimens in which rare erath oxide is dispersed as coarse particles at the grain boundaries. Therefore, the spray dry method is a hopeful process to produce rare earth oxide dispersion tungsten alloys.抄録全体を表示PDF形式でダウンロード (2978K) -
Naoya Enomoto, Masumi Katsumoto, Zenbe-e Nakagawa1993 年 40 巻 7 号 p. 713-717
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーHigh-power ultrasound was applied during the hydration of MgO fine powders in order to see the effect of ultrasound in a heterogeneous fluid where the dissolution of MgO particles and the precipitation of Mg(OH)2 are included. The results obtained showed that the irradiation of ultrasound fairly promotes the dissolution of MgO, which is the rate-determining step in the reaction, and that it promotes the nucleation of Mg(OH)2, which has resulted in the reduction of crystallite sizes of the Mg(OH)2 precipitated.抄録全体を表示PDF形式でダウンロード (2531K) -
Shigetoshi Muranaka, Naoichi Yamamoto1993 年 40 巻 7 号 p. 718-722
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーIndium oxide films were reactively deposited at oxygen pressures of 3x10-3-0.3Pa and at substrate temperatures of 25-200°C. The influence of the oxygen pressure on the electrical resistivity of films and the light transmission was investigated. At a substrate temperature of 25°C, the resistivity of the films was drastically increased with increasing oxygen pressure, while at 100°C, the behavior of the film resistivity was rather complicated. At 150 and 200°C, the resistivity of films was gradually increased as the oxygen pressure increased. The light transmission of films was increased with increasing oxygen pressure at 25-200°C. The dependence of the film resistivity and transmission on the oxygen pressure was discussed based on the structure of films.抄録全体を表示PDF形式でダウンロード (244K) -
山口 敏彦, 本田 忠敏, 井畑 康, 三浦 秀士, 安藤 新二1993 年 40 巻 7 号 p. 723-729
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーThe behavior of fatigue crack growth of sintered iron and steel compacts were investigated in comparing with that of the nodular graphite cast irons for various stress ratios and specimen thickness by using 1/2 compact type specimens, prepared by single pressing, sintering and machining.
The results obtained were summarized as follows:
1) Under the constant stress ratio, the relationship between fatigue crack growth rate(da/dN) and stress intensity factor range(ΔK) of sintered compacts was dependent on the density and the structure. However, the relationship between da/dN and ΔK/E normalized by Young's modulus(E) was linear independently of the density in the sintered iron compacts. Under the same ΔK, da/dN of the sintered compacts was slightly bigger than that of the nodular graphite cast irons.
2) As the stress ratio is increased, the fatigue crack growth curves of sintered compacts were shifted to the lower stress intensity factor range. The threshold in stress intensity factor(ΔKth) was decreased with an increase in the stress ratio.
3) Effects of specimen thickness on the fatigue crack growth in sintered compacts did not appear in the range of 10.0mm to 12.5mm.抄録全体を表示PDF形式でダウンロード (1867K) -
金子 武1993 年 40 巻 7 号 p. 730-735
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーAn impact test was carried out to evaluate the effects of notch shape and tungsten content on the impact absorbed energy of Iiquid phase sintered W-Ni-Fe heavy alloys.
The microstructure of the alloys consists of rounded, single crystal tungsten grains in a matrix phase. Several samples of different mechanical properties, and of different notch shapes and tungsten contents of the test pieces were tested, and, as a result the fractography and the fracture patterns were observed by using scarring electron microscopes.
It was confirmed that the notch shape influenced on the impact absorbed energy and the bonding force of the interface between the matrix phase and the tungsten grain.
By considering these characteristics, a fracture model of W-Ni-Fe heavy alloy was proposed after the discussion of fracture mechanism抄録全体を表示PDF形式でダウンロード (3072K) -
寺田 修, 斎藤 実, 土屋 信次郎, 鈴木 寿1993 年 40 巻 7 号 p. 736-738
発行日: 1993/07/15
公開日: 2009/12/04
ジャーナル フリーThe factors affecting the structure having sheet-like WC phases were studied in WC-βt-Co cemented carbide. It was found that the sheet-like phases were apt to form in the structure as the grain size of starting WC powder decreased by ball-milling and as the carbon content of alloy increased, in close relation to sintering temperatures and binder and βt contents. It was noted that the sheet-like phases formed also in the alloy prepared by solid-phase sintering.抄録全体を表示PDF形式でダウンロード (3596K) -
鈴木 寿, 斎藤 実, 寺田 修, 土屋 信次郎1993 年 40 巻 7 号 p. 739-742
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーIt is widely known that the nitrogen contained cermet has been used commercially for cutting tool material because of its excellent creep strength, though the cermet has many faults such as the appearance of pores in the structure, lacking of uniformity of mechanical properties, etc. Then, the study on, creep strength of nitrogen free cermet was made in relation to different factors to find out a high creep strength almost the same as that of nitrogen contained one. It was made clear that the nitrogen contained cermet could be replaced by the nitorgen free one having low carbon, fine grain size and adequate amount of Mo2C at a fixed binder content.抄録全体を表示PDF形式でダウンロード (2904K) -
植木 光生1993 年 40 巻 7 号 p. 743-750
発行日: 1993/07/15
公開日: 2009/05/22
ジャーナル フリーNitrogen contained titanium carbide based cermet has come to be widely used for cutting tools material. However, the factors affecting the cutting performance seem not to be fully clarified until now. This paper is a summary of the results of recent studies by the present authors, on the role of additional carbides, structure changes by annealing, the decrease of the amount of binder in the surface layer of the alloy, influence of nitrogen adding methods and so forth.抄録全体を表示PDF形式でダウンロード (6219K)
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